Our environment provides us with a lot – from food, places to boat and swim, and wildlife to enjoy…the list goes on. So when these areas become polluted and unhealthy, it isn’t just bad for the environment, it’s also bad for us. We lose the beautiful things we get from the environment, threaten biodiversity and influence the global climate change. However, thanks to the evolution of remediation technology, we are able to diminish some of the damaging effects that these pollutants have had on our environment.
Environmental remediation is the removal of pollutants or contaminants from water and soil. These environmental factors are polluted as a result of the use of fertilizers, pesticides, some industrial activities, indiscriminate dumping of hazardous chemicals and other pollutants into lakes, rivers, streams and onto unused land.
These contaminants in the environment can look and smell pretty nasty, but their impacts go beyond just aesthetics. Some pollutants resist breakdown and accumulate in the food chain. These pollutants can be consumed or absorbed by fish and wildlife, which in turn may be eaten by us. Chemicals can also get into sediments, impacting large coastal areas, threatening human health, and reducing the economic well-being of regions that depend on the healthy environment.
To help with environmental remediation, one can employ the services of an Environmental Consultant. These services help reduce/eliminate the sources of these pollution and help restore / protect the environment. There are steps to environmental remediation which usually includes; site assessment, stakeholders’ input, classification of remediation and remediation technologies to adopt.
Environmental remediation usually begins with a site assessment to determine the cost of remediation, as well as the technology that would be the most appropriate for the particular site. Assessments are also made to identify any potential hazards to the workers who will be working on the project and to evaluate the impact that pollution might have on the local community, as well as its overall environmental impact.
Contaminated or polluted sites are accessed to ascertain the level of contamination. Net benefits of the remediation works to the affected community should be put into consideration — remediation should do more good than harm; Waste generation from remediation should be reviewed because remediation is generally a waste generating activity, and the amounts and properties of generated wastes need to be considered in the decision making process; Ethical issues should be considered as remediation may affect people’s lives and their environment, including how they live.
The historical use of the site and the type of materials used and produced on site will determine:
- The assessment strategy
- Type of sampling
- Chemical analysis to be done.
Often nearby sites are also contaminated even where the current land use seems harmless. Topsoil as well as surface and groundwater of nearby properties should also be tested, both before and after any remediation.
Stakeholders’ Input Matters
An important factor for a successful remediation project is for those people whose lives are affected by the contamination to be involved in and to contribute to the remediation process as they have a stake in the end result. It is not only an ethical matter but a moral obligation to involve various stakeholders in the remediation process. Typically, a remediation project has a series of stakeholders, including, for example, the immediate affected population and communities, operators, regulators, non-governmental organizations as well as other segments of the society as a whole that may wish to have a say in the project decision making process (Getting to the core of environmental remediation by International Atomic Energy Agency). Listening to stakeholders’ opinions, capturing their perspectives and taking them into account from the very beginning of the remediation process assists the decision making process for taking the most appropriate approach.
Types of environmental remediation
Environmental remediation is carried out on soil, sediment, groundwater, and surface water. Water remediation includes both groundwater and surface water, whereas soil remediation includes topsoil, subsoil, and sediment. Soil and waterremediation may be conducted separately or together, depending on the type and extent of the pollution.
Water remediation is the process of removing contaminants from water. Surface water in lakes, streams, and rivers canbe directly contaminated by pollutants released directly into the water or by runoff from the ground. Groundwater canbecome polluted by contaminants leaching through the soil and sediment above it or as the result of industrial practices suchas mining or drilling for natural gas and oil.
Soil remediation refers to methods used to purify and revitalize the soil. Soil contamination is caused by many of thesame factors that cause groundwater contamination. Often, the soil and groundwater are contaminated from the same source and both must be remediated at the same time. Soil contamination can result from chemical spills, industrial activity, and the use of certain fertilizers and pesticides.
Remediation technologies are many and varied but can be categorized into ex-situ and in-situ methods.
- In-situ remediation methods treat the contamination on the site without removing soil or ground water
- Ex-situ remediation involves excavating soil, sediment or groundwater and treating it, before returning it to its original state.
Traditional remediation approaches consist of
- soil excavation
- disposal to landfill and groundwater “pump and treat”.
In-situ technologies include but are not limited to:
- solidification and stabilization,
- soil vapor extraction,
- permeable reactive barriers,
- monitored natural attenuation,
- chemical oxidation,
- steam-enhanced extraction and
- in situ thermal desorption
A case study of a crime scene contaminated with blood and bodily fluids that can pose health risks such as hepatitis, HIV, and MRSA is presented. The method to adopt in this scenario is bioremediation. Rather than using standard cleaning agents like bleach or ammonia, crime scene cleaners can use enzyme cleaners to rid the scene of harmful substances.
Another example is the clean-up of a contaminated soil where human activity has introduced many toxic substances into the soil and groundwater. During this clean up, microbes are introduced into the soil and these microbes utilize chemical contaminants in the soil as an energy source and, through oxidation-reduction reactions, metabolize the target contaminant into useable energy for microbes.
Another scenario is the Oil spill cleanup: You may remember the Deepwater Horizon oil spill that happened in 2010, where 3.19 million barrels of oil spilled off the Gulf of Mexico. Due to the effectiveness and lower cost of bioremediation, two methods were used to clean up after the Deepwater Horizon oil spill.
o Bioaugmentation: The injection of a small amount of oil-degrading microbes into an affected area.
o Bio stimulation: The addition of nutrients to stimulate the growth of innate oil-degrading microbes to increase the rate of remediation.
We live in an ecosystem where the action of one has the potential to affect the many. This can be a good or a bad thing, depending on what the action is. Our mistakes have polluted the environment that we live in. A very good example is the oil spill contamination of Ogoni land, Nigeria, an environmental remediation proven to be the world’s most wide-ranging and long term oil clean-up exercise ever undertaken. It is good we are waking up and owning this fact and also trying to reverse the damage. The good news is that every positive action counts. The small effort you make towards a greener environment can start a healing ripple effect. We may still save what is left of our natural resources and make the world a better place to live in for our future generation.
There are a lot of environmental remediation issues in Nigeria today and Ashawa Consults Ltd provides a wide range of solutions to these issues. Take advantage of our expertise and call our environmental team today for a rehabilitation solution to suit your site.
“The environment and the economy are really both two sides of the same coin. If we cannot sustain the environment, we cannot sustain ourselves”- Wangari Maathai